AQA GCSE Physics -Paper 2
Scalar - Answers -quantities with only magnitude such as speed, distance, time and
mass.
Vector - Answers -quantities with a magnitude and direction e.g. acceleration, force
momentum and weight. A vector quantity can be represented as an arrow, the size
representing the magnitude and the direction, the direction.
Non-contact force - Answers -the objects are physically separate e.g.
magnetism/gravity/electrostatic.
3 non-contact forces - Answers -magnetism
gravity
electrostatic
Contact force - Answers -objects are physically touching .
3 contact forces - Answers -friction
resistance
tension
Gravity - Answers -Weight is the force acting on an object due to gravity, it acts on an
objects 'centre of mass' and is directly proportional to mass
Weigh Equation - Answers -Weight = mass x grav. field strength
Resultant forces - Answers -A number of forces acting on an object may be replaced by
a single force that has the same effect as all the original forces acting together, this
single force is the called the resultant force.
In a tug of war, 1000N to the left and 800N to the right. The resultant force is 200N to
the left
Free-Body force diagrams - Answers -When an object is acted on by more than one
force you can draw a free-body force diagram to work out the resultant force on the
object. It shows the forces acting on an object without any other objects or other forces
shown. Each force is shown on the diagram by a vector, which is an arrow pointing in
,the direction of the force. ( the normal force is that component of the contact force that
is perpendicular to the surface that an object contacts)
How to resolve forces (force diagram steps) - Answers -1. Decide on a scale of N per
cm.
2. Draw the 2 given forces, giving respect to their length (more cm if more N) and the
angle that you are given
3. Draw a line connecting the end of the 2 other lines to form a triangle
4. Measure the length of this line, then convert it to N by using the scale
Relationship between Joules and work done - Answers -When a force causes and
object to move, work is done on the object so when the force causes displacement. One
joule of work is done when a force of 1 newton displaces an object 1 metre. 1 Joule = 1
newton-metre.
Equation for word done - Answers -work done = force x distance
Elastic Deformation - Answers -When an elastic object is stretched, bent, twisted or
compressed it will return to its original form
Inelastic Deformation - Answers -Polyethene bags will not return to their original shape
after being deformed, this is inelastic.
Hooke's Law - Answers -The extension of an elastic object is directly proportional to the
force applied as long as the limit of proportionality is not exceeded:
Equation for force (Hooke's law) - Answers -force = spring constant x extention
Extension and compression's relationship with elastic potential energy explanation -
Answers -A force that stretches or compresses a spring does work and elastic potential
energy is stored in the spring, provided the spring is not elastically deformed, the work
done and elastic potential energy are equal. Before the limit of proportionality is
breeched the relationship is linear (directly proportional) afterwards it is non-linear
Elastic potential energy equation (given) - Answers -Elastic potential energy = 1/2 x
spring constant x extension^2
Moment meaning - Answers -The turning effect of a force is called its 'moment'
Moment equation - Answers -moment = force x distance
Balancing - Answers -If an object is balanced the clockwise moment is equal to the
anticlockwise moment.
, Levers - Answers -A lever consists of a load, effort and pivot, levers use moments to
multiply a force, they allow a larger force to act on the load that is supplied by the effort.
Engine Gears - Answers -Engine gears have two main jobs, producing torque and
speed, however they are inversely proportional so gears are made to make a
compromise between the two in any given situation.
When starting a car we want high torque, which means being able to carry a greater
load , and consequentially less speed. In low gears this is achieved as... - Answers -1.
The engine causes a small cog on the engine axle to rotate.
2. The small cog on the engine axle is connected to a larger cog on the wheel axle,
which increases the torque (moment) exerted.
3.A high turning force but low speed is exerted on the wheel (low gear)
When a car is already moving, we want a high speed which is achieved as... - Answers
-1.The engine causes a larger cog on the engine axle to turn.
2.The larger cog on the engine axle is connected to a smaller cog on the wheel axle,
causing a high rate of rotation, but a low turning force.
3. The wheel rotates quickly, causing a high speed
Unit for pressure - Answers -Pressure is a measure of force per unit of area, the si unit
is Pascals (Pa) which is one N/m^2
Pressure Equation - Answers -Pressure = force normal to the surface/area
Manometer with oil and water - Answers -The pressure is equal at each end of the tube,
so the less dense oil is higher.(p=hdg)(on sheet)
Buoyancy - Answers -The partially or fully submerged object experiences more
pressure at the bottom that on top, this creates a resultant up thrust force called
buoyancy.
Why objects float - Answers -An object will rise or float if it is less dense than the
substance it is in or if it displaces an amount of the substance that it is floating in greater
than it weights, steel ships have a lot of air in them and therefore weigh less than the
equivalent amount of water that the ship displaces, so it floats this is because the up
thrust from the pressure is greater than the down force of the weight.
Atmospheric pressure and how it varies by altitude - Answers -Air pressure is created
by air molecules colliding with a surface, if we consider the density of these particles
being same at all attitudes, the fact the volume of the earth's atmosphere increases as
Scalar - Answers -quantities with only magnitude such as speed, distance, time and
mass.
Vector - Answers -quantities with a magnitude and direction e.g. acceleration, force
momentum and weight. A vector quantity can be represented as an arrow, the size
representing the magnitude and the direction, the direction.
Non-contact force - Answers -the objects are physically separate e.g.
magnetism/gravity/electrostatic.
3 non-contact forces - Answers -magnetism
gravity
electrostatic
Contact force - Answers -objects are physically touching .
3 contact forces - Answers -friction
resistance
tension
Gravity - Answers -Weight is the force acting on an object due to gravity, it acts on an
objects 'centre of mass' and is directly proportional to mass
Weigh Equation - Answers -Weight = mass x grav. field strength
Resultant forces - Answers -A number of forces acting on an object may be replaced by
a single force that has the same effect as all the original forces acting together, this
single force is the called the resultant force.
In a tug of war, 1000N to the left and 800N to the right. The resultant force is 200N to
the left
Free-Body force diagrams - Answers -When an object is acted on by more than one
force you can draw a free-body force diagram to work out the resultant force on the
object. It shows the forces acting on an object without any other objects or other forces
shown. Each force is shown on the diagram by a vector, which is an arrow pointing in
,the direction of the force. ( the normal force is that component of the contact force that
is perpendicular to the surface that an object contacts)
How to resolve forces (force diagram steps) - Answers -1. Decide on a scale of N per
cm.
2. Draw the 2 given forces, giving respect to their length (more cm if more N) and the
angle that you are given
3. Draw a line connecting the end of the 2 other lines to form a triangle
4. Measure the length of this line, then convert it to N by using the scale
Relationship between Joules and work done - Answers -When a force causes and
object to move, work is done on the object so when the force causes displacement. One
joule of work is done when a force of 1 newton displaces an object 1 metre. 1 Joule = 1
newton-metre.
Equation for word done - Answers -work done = force x distance
Elastic Deformation - Answers -When an elastic object is stretched, bent, twisted or
compressed it will return to its original form
Inelastic Deformation - Answers -Polyethene bags will not return to their original shape
after being deformed, this is inelastic.
Hooke's Law - Answers -The extension of an elastic object is directly proportional to the
force applied as long as the limit of proportionality is not exceeded:
Equation for force (Hooke's law) - Answers -force = spring constant x extention
Extension and compression's relationship with elastic potential energy explanation -
Answers -A force that stretches or compresses a spring does work and elastic potential
energy is stored in the spring, provided the spring is not elastically deformed, the work
done and elastic potential energy are equal. Before the limit of proportionality is
breeched the relationship is linear (directly proportional) afterwards it is non-linear
Elastic potential energy equation (given) - Answers -Elastic potential energy = 1/2 x
spring constant x extension^2
Moment meaning - Answers -The turning effect of a force is called its 'moment'
Moment equation - Answers -moment = force x distance
Balancing - Answers -If an object is balanced the clockwise moment is equal to the
anticlockwise moment.
, Levers - Answers -A lever consists of a load, effort and pivot, levers use moments to
multiply a force, they allow a larger force to act on the load that is supplied by the effort.
Engine Gears - Answers -Engine gears have two main jobs, producing torque and
speed, however they are inversely proportional so gears are made to make a
compromise between the two in any given situation.
When starting a car we want high torque, which means being able to carry a greater
load , and consequentially less speed. In low gears this is achieved as... - Answers -1.
The engine causes a small cog on the engine axle to rotate.
2. The small cog on the engine axle is connected to a larger cog on the wheel axle,
which increases the torque (moment) exerted.
3.A high turning force but low speed is exerted on the wheel (low gear)
When a car is already moving, we want a high speed which is achieved as... - Answers
-1.The engine causes a larger cog on the engine axle to turn.
2.The larger cog on the engine axle is connected to a smaller cog on the wheel axle,
causing a high rate of rotation, but a low turning force.
3. The wheel rotates quickly, causing a high speed
Unit for pressure - Answers -Pressure is a measure of force per unit of area, the si unit
is Pascals (Pa) which is one N/m^2
Pressure Equation - Answers -Pressure = force normal to the surface/area
Manometer with oil and water - Answers -The pressure is equal at each end of the tube,
so the less dense oil is higher.(p=hdg)(on sheet)
Buoyancy - Answers -The partially or fully submerged object experiences more
pressure at the bottom that on top, this creates a resultant up thrust force called
buoyancy.
Why objects float - Answers -An object will rise or float if it is less dense than the
substance it is in or if it displaces an amount of the substance that it is floating in greater
than it weights, steel ships have a lot of air in them and therefore weigh less than the
equivalent amount of water that the ship displaces, so it floats this is because the up
thrust from the pressure is greater than the down force of the weight.
Atmospheric pressure and how it varies by altitude - Answers -Air pressure is created
by air molecules colliding with a surface, if we consider the density of these particles
being same at all attitudes, the fact the volume of the earth's atmosphere increases as
